DURHAM, N.C. (AP) -- So much has changed for Casey Carroll since he last stood on the Duke sideline during the NCAA men's lacrosse tournament.

The former All-American defenseman is now a husband, father, former U.S. Army Ranger, combat veteran and graduate student hoping to return for a final unused year of eligibility. A knee injury prevented that this year, meaning the 28-year-old Carroll - the last active member of the 2006 team scarred by false rape allegations against three players - will be here for Duke's NCAA opener against Loyola of Maryland on Sunday to feel close to the sport he hopes to play again next year.

"I think it just lets me know that the passion is all still there," Carroll said. "I don't think it ever leaves you."

Carroll first arrived on campus nearly a decade ago as a freshman from Baldwin, N.Y. He was part of Duke's rise to national-power status by reaching the 2005 NCAA final, its fall a year later when the later-discredited rape scandal led to the cancellation of the second half of the season, then the climb back to the 2007 championship game.

The Blue Devils lost to Johns Hopkins by one goal in both NCAA finals.

Carroll graduated in 2007 and enlisted in the Army's 3rd Battalion, 75th Ranger Regiment and served about 4 1/2 years with tours in Iraq and Afghanistan. He avoided serious injury, was honorably discharged in February 2012 and re-enrolled at Duke for the fall semester.

He practiced with the team through fall camp before suffering a torn knee ligament in January for the second time in his career, the first coming four games into the 2006 season.

Still, Carroll said he feels like he's "playing with house money."

"I don't think about any unfinished business," Carroll said. "It was never about that sort of stuff for me because I'm just so proud of the time I did have at Duke the first time. ... It's just about coming back here and having a blast and getting 40-something new friends that I hadn't had."

While recovering from surgery, Carroll occasionally helped at practice and offered observations from the sidelines during home games and trips to nearby rival North Carolina.

"With the life experience he brings to the table, when you look over your shoulder and see him there, you're kind of reassured," senior midfielder Greg DeLuca said. "He has such a calming presence because he's never rattled out there. This has got to be the most fun thing in the world especially after some of the things that he's done."

Carroll is attending Duke's Fuqua School of Business through help from the GI Bill and the Yellow Ribbon Program, which covers costs beyond the GI Bill's limits.

He's also juggling family demands. He and his wife, Erin, welcomed son Casey Patrick last September and they're expecting a second child this November.

The NCAA typically gives athletes four years to compete within a 5-year window, though the NCAA granted a fifth year of eligibility to non-seniors from the 2006 team to replace the year cut short by the scandal.

The clock paused during Carroll's enlistment then restarted when he returned to school. Duke will petition the NCAA this summer for a sixth-year waiver allowing Carroll to play a final season in 2014.

"If (the knee injury) is the worst thing that happens to him in life - knock on wood - and he doesn't get his next year of eligibility and this was the end of it, then we'd be happy," said Erin Carroll, a former Duke soccer player. "Because there's a lot of people that aren't as lucky."

If the request is approved, coach John Danowski - whose first year here was Carroll's last - said Carroll can take as long as needed to decide on returning to the team amid school and family demands.

"Whatever he wants," Danowski said. "He's earned that."

Either way, Carroll has loved being back and hopes there's more memorable moments to come.

"You don't realize how much fun and what a great experience it is until it's gone," Carroll said. "Being that one in a million people that gets to come back, then you fully understand all you've been through, all you've ever worked for and how great that was. And to get to do that one thing that you love so much one more time, you can't instill that in a 22-year-old kid or an 18-year-old."

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